Exhaust pipe closure mechanism



W. S. HESS May 4, 1 965 EXHAUST PIPE CLOSURE MECHANISM Filed Feb. 5,1963 1 W a 0/0 w 4 m m z Q 2 g a .H L a w n z a a m 3 4 Z J l w m m nHIIHIIHHMT w? a w, .r....|.| ..Hl..U. fiHHH lum mfi .i m 6mm w llll L Ai UH INVENTOR wmw s. mew

ATTORNEYS United States Patent O 3,181,451 EXHAUT PIEE QLQdURE MEQHANESMWynn S. Hess, Kent, Wests, assignor of one-fourth to Delbert J. BarnardFiled Feb. 5, 1963, Ser. No. 256,336 6 Claims. ((Zl. 98-49) Thisinvention relates to closure mechanisms for preventing rocks, debris andmoisture from entering vertically extending exhaust pipes (sometimestermed stacks) of vehicles such as bulldozers, tractors, etc. duringperiods when such vehicles are standing idle in the open, and duringcertain periods of use. More particularly, the present invention relatesto closure mechanisms situated wholly inside either the exhaust pipe ora tubular extension thereof, both when said mechanism is open and whenit is closed, such arrangement preventing the closure mechanism frombeing struck and damaged, or removed, by overhead limbs, etc. duringperiods of vehicle operation, and also protecting such closure mechanismfrom the effects of Wind, both during periods of vehicle operation andduring periods of vehicle shutdown.

Reference is made to the first page of Stade et al., US. Patent2,983,216, issued May 9, 1961, wherein a thorough presentation is madeof the problems encountered in the utilization of vertically extendingexhaust pipes with the internal combustion engines of bulldozers,tractors, etc. The exhaust pipe closure mechanisms of the presentinvention are in the nature of improvements over exhaust pipe closuremechanisms of the lid type, such as the one disclosed in the Stade etal. patent, for example. The exhaust pipe closure mechanism of the Stadeet al. patent is characterized by a lid or cover" pivotally mountedbetween laterally extending ear portions of a clamp used to secure suchmechanism to the exhaust pipe. The lid or cover is provided with abalance arm or counterweight and is movable between a horizontal closedposition to a somewhat vertical open position. The principaldisadvantage of this form of closure mechanism stems from the fact thatit is situated wholly outside of the exhaust pipe and hence isunprotected from being struck and damaged, or even removed, by overheadlimbs and the like. Lid damage or destruction is particularly a problemwhere the vehicle is a bulldozer, as bulldozers are commonly employedfor clearing in brushy and forest areas where overhead objects such aslimbs exist in abundance. A further disadvantage of the lid type closuremechanism incident to their exterior location is that they are affectedby wind action both during periods of vehicle operation and duringperiods of vehicle shutdown. A still further disadvantage of lid typeclosure mechanisms is that they are easily opened by children playing onthe vehicle when it is idle, making it easy for such children to insertsuch objects as sticks, rocks, sand, etc. into the exhaust pipe, and aswould be expected, in most cases said objects cause serious injury tothe engines.

The principal object of the present invention is to produce a closuremechanism which does not posses any of the foregoing disadvantages.

One form of closure mechanism constructed in accordance with the presentinvention is characterized by a cylindrical tube detachably mount-ableon the terminal end portion of a vertically extending exhaust pipe by aclamping ring, or the like, with such cylindrical tube housing a pair ofclosure members or flaps pivotally mounted on opposite sides of atransverse extending pin and movable between substantially horizontalclosed positions and substantially vertical open positions, and withmovement of said flaps from their closed to their open ice positionbeing effected during engine operation by the exhaust gases flowingupwardly through said cylindrical tube, and with closure of said flapsbeing efiected by gravitational return of the flaps to theirsubstantially horizontal positions when the engine is turned off and theemiaust gases cease to flow through said cylindrical tube. Additionalfeatures of this form of the invention include a transverse extendinggutter member situated below said pin and serving to collect and disposeof any moisture entering the generally cup-shape zone situated above theflaps when they are closed, with such gutter member being rigidlyconnected at its respective ends to diametrically opposed portions ofthe cylindrical tube.

This first form of the invention also includes a seat forming member ormembers situated (at least in part) laterally of the pin and serving tolimit the downward pivotal movement of said flaps, and stop meanssituated substantially vertically above at least a portion of said pinand serving to prevent pivotal movement of each flap from itssubstantially vertical open position towards the closed position of theother flap. Thus, the seat forming member or members establishes theclosed positions of the flaps, and the stop means establishes the openpositions of the same.

In a second form of the invention, the seat forming member is in theshape of a ring and supports both the pin onto which the flap membersare pivotally mounted and the gutter member. Such ring and itsassociated elements (the flaps, gutter, etc.) are inserted into the openend of the exhaust pipe and once properly oriented therein is secured inplace by means of a plurality of circumferentially arranged metal screwsor the like. In this form of the invention a pair of metal screws or thelike constitute the stop means.

Both of these forms of the present invention involve a relatively smallnumber of easily formed components, and are thus both practical andinexpensive to manufacture. In addition, both forms of the inventionpresent an exhaust pipe closure mechanism that is both efiicient anddurable, even under condition of hard use over long periods.

These, together with other objects and advantages, which will becomesubsequently apparent, reside in the details of construction andoperation of certain typical embodiments of the invention presently tobe described, reference being bad to the accompanying drawings forming apart of this application, wherein like numerals refer to like partsthroughout, and in which:

FIG. 1 is a sectional view of one form of the present invention, showingin solid line the closure members in their closed positions, and inbroken line such members in their open positions, said sectional viewbeing taken substantially on line 1-1 of FIG. 2;

FIG. 2 is a top plan view of the form of the invention shown in FIG. 1;

FIG. 3 is a view taken substantially at right angles to FIG. 1, showingthe cylindrical member and the seat ring in section, and showing thegutter and the closure members in elevation, with such closure membersoccupying their substantially vertical positions;

FIG. 4 is a fragmentary perspective View of one form of the stop meansusable to prevent pivotal travel of the closure members past asubstantially vertical position;

FIG. 5 is a perspective view of a modified form of the invention whereinthe closure members, the pin and the gutter are carried by the seatring, and such ring is inserted into the vertically extending exhaustpipe of internal combustion engine and secured in position by means of aplurality of circumferentially spaced metal screws, or the like, andadditional metal screws form the stop means, such view showing theattachment and screws in solid lines and the exhaust pipe in brokenlines; and

FIG. 6 is a perspective view of the exhaust pipe attachment of FIGS.1-3, showing the means used for securing such attachment to the endportion of a vertically extending exhaust pipe, and in addition showingdirt removal openings which may be optionally provided in the wall ofthe cylindrical member above the closure means. The form of theinvention illustrated in FIGS. 1-4 and 6 is in the nature of a clamp-onattachment and comprises a cylindrical tube or duct member 10 detachablysecured to the terminal end portion of a vertically extending exhaustpipe 12, as by a conventional clamping ring 14 (FIG. 6), for example,and forming a part of the exhaust system. The lower portion of tube 10is. preferably slotted at spaced intervals as at 16 in FIG. 6, toprovide resiliency so that tube 10 can be drawn into tight engagementwith exhaust pipe 12. I

A pin 18 forming a part of the closure mechanism laterally spans theinterior of tube 10 and connects at its respective ends to the wall oftube 10 at diametrically opposed locations. A first'flap or closuremember 25) is pivotally connected to pin 18 by means of binge 22. Asecond flap or closure member 24 is pivotally connected to pin 18 byhinges 26, 28. As most clearly shown in FIG. 2, hinges 22, 26, 28 aresubstantially coaxially arranged, with hinge 22 being approximatelytwice the length of hinges 26, 28 (or substantially equal to theircombined lengths), and with hinge 22 being interposed between hinges 26,28. Hinge 22 is an integral portion of flap 20, such portion beingcurled back on itself to define a substantially cylindrical bore throughwhich pin 18 extends. Hinges 26, 28 form integral portions of flap 24,and in identical fashion to hinge 22 they curl back on themselves todefine cylindrical bores for the reception of pin 18. As is apparentfrom FIGS. 13 and the foregoing description, the construction andarrangement of hinges 22, 26, 28 with pin 18 is similar to theconstruction and arrangement' of the knuckle joint of a conventionalbutt hinge.

In FIG. 1 a ring-like seat member 30 is shown extending around the fullcircumference of the inner sur- 'face of tube 10, with its upper edge 32forming both a seat for flap 20 on one side of pin 18 and a seat forflap 24 on the opposite side of pin 18. Rim edge 32 is preferablyconfigured to seat flaps 20, 24 in the position shown in FIG. 1, i.e.with such flaps 20, 24 sloping downward slightly from the tube walltowards pin 18 for a reason hereinafter discussed. However, rimv edge 32could just as well be configured to seat flaps 20, 24 Within the samehorizontal plane, as such arrangement would produce no adverse results.

Flaps 20, 24 are preferably constructed from a relatively lightweight,heat resistant sheet metal. The outer edges of the flaps 20, 24 are cutso that they substantially contact the inner surface of wall 10 entirelyaround its circumference when closed. Thus, in embodiments wherein rimedge 32 is configured to seat flaps 20, 24 Within a common horizontalplane, flaps 20, 24am essentially semi-circular in shape. In embodimentswherein the upper edge 32 of ring 30 is of butterfly form, as shown, themiddle ordinates of flaps 20, 24 are slightly larger than the insideradius of tube 10 and such flaps 20, 24 are substantiallysemi-elliptical in form.

Although ring 30 and its upper edge 32 are shown as extending around theentire inside circumference of tube 10, an alternative arrangement wouldbe to provide flaps 20, 24 with relatively short seat formingmemberspreferably positioned below flaps 20, 24 in thevicinity of wheresection 11 is taken, i.e. at the intersection of the middle ordinates offlaps 20, 24'with wall 10. Such seat forming members could take a widevariety of shapes or forms, and still fall within the scope of thepresent invention. For example, a three-sided cut could be made in oneor more appropriate locations in the cylindrical wall of tube 10 and thetab defined between said cuts be pushed in to form the seat formingmember.

A gutter member 34 is situated below the clearances existing betweenflap 20 and hinges 26, 28, between hinge 22 and fiap 24, and between thehinges themselves. Gutter 34 extends substantially coaxially with pin 18and connects at its respective ends to the inner surface of tube 10, asby welding, for example. Drainage openings 36, 38 are extended throughtube 10 in the vicinity of the respective ends of gutter 34.

Stop means such as louvers 40, 42 (most clearly illustrated in FIG. 4)are provided above pin 18 to prevent pivotal movement of flaps 2t), 24past substantially vertical positions (as shown in FIG. 1). 7 Duringperiods of engine shutdown, flaps 20, 24 occupy the position shown bysolid lines in FIGS. 1 and 2, such being their closed positions. Anymoisture collected on top of flaps 20, 24 is drained inwardly towardsthe hinges and seeps through the clearances and is collected by' gutter34. The moisture .then flows out of gutter 34 through drainage openings36, 38. Thus, moisture is positively prevented from entering the exhaustpipe 12 (and in turn the engine) during periods of engine shutdown.During periods of engine operation the exhaust gases discharging fromexhaust pipe 12 pivotally move flaps 20, 24 to their substantiallyvertical, open positions (shown by broken lines in FIG. 1 and by solidlines in FIG, 3). As most clearly shown in FIG. 1, the stop members 40,42 prevent pivotal movement of each of said flaps past its open positiontowards the closed position of the other. The provision of at least oneof said stop members is deemed essential in order to assure properreturn of both flaps to their respective closed positions. If no stopmember or members were provided, both of the flaps might pivotally dropon the same side of pin 18, leaving the opposite side of tube 10 openduring engine shutdown. It is evident by now that soon as the engine isturned off, flaps 20, 24 will return to their respective closedpositions by the action of gravity. Small metal counterweights such aselements 44, 46 are optionally provided on the under surfaces of flap-s20, 24 to increase the weight of such flaps 20, 24, and in turn theirtendency to drop to their closed positions.

Tube 10 is also optionally provided with a series of circumferentiallyspaced openings, one of which is desig nated 48 in FIG. 6, forfacilitating removal of dirt, etc. from the cup-shaped zone existingabove flaps 20, 24 when they occupy their closed positions. Dirt mightaccidentally dislodge from an overhanging bank and fall into suchcup-shaped zone, or might be placed therein by a child playing on thevehicle when it is standing idle during non-working hours. Regardless ofhow its gets into the cup-shaped zone, the dirt can easily be pushed outthrough said openings 48 by a stick, screwdriver, etc. inserted downthrough the open top end of tube 10.

During engine operation tail pipe 12 vibrates to some extent, with theamount of vibration varying with each piece of equipment and in somecases being quite substantial in amount. One problem experienced withclampon attachments is that such vibration tends to loosen the clamp andallow the attachment to creep downwardly on the exhaust pipe; When thisoccurs in the case of conventional lid type mechanisms, such as shown inaforementioned Patent 2,983,216, the lid is prevented by the exhaustpipe from returning to its closed position. If such condition is notnoticed and corrected by the operator before leaving his equipment atthe end of the working day, the exhaust pipe is left uncovered duringthe idle hours. above described attachment of the present invention. Ifthe seat forming ring 30 is employed, its lower rim edge abuts the upperrim edge of exhaust pipe 12 and in that way limits downward travel oftube 1% in the event clamp 14*vibrates loose. Also, if tabs or somesimilar seat forming means is used in place of ring 30, downward travelof tube'ltl is limited or checked by gutter 34. Thus, tube 10 cannotcreep downwardly on exhaust pipe This is not the case with respect tothe 12 to an extent where such exhaust pipe 12 interferes with theproper operation of closure members 29, 24. During engine operationgutter 34 also serves to protect hinges 22, 26, 28 from direct exposureto the hot exhaust gases or flame sometimes issuing from exhaust pipe12. Thus, gutter 34 may also be termed a heat shield, a heat baffle, orsimply a baffle.

Flaps 2t), 24, in both their open and closed positions, are locatedwholly within tube and are thus not exposed to wind action duringperiods of engine shutdown, and are also protected from damaging blowsby overhead limbs, etc. during periods of engine operation. Furthermore,due to their unique construction, flaps 2t}, 24 are extremely difficultto open by a child sticking a finger or other object down into the openend of tube 10 for that purpose.

The form of the invention shown in FIG. 5 is in the nature of aninternal attachment, insertable into the open end of verticallyextending exhaust pipe 12' and secured in place therein by means of aplurality of circumferentially spaced metal screws 48, for example. Pin18 is supported at its ends by upstanding ear portions 5t 52 of seatforming ring 39'. Gutter 34' is also connected at its ends (e.g. bywelding) to ring and discharge opening 5 is provided in ring 30' in thevicinity of each end of gutter 34, such discharge openings 54 aligningwith a second set of discharge openings 56 drilled through the wall ofexhaust pipe 12. In this form of the invention a pair of metal screws58, 60, or the like, constitute the stop means for preventing pivotalmovement of each flap past its substantially vertical, open positiontowards the substantially horizontal, closed position of the other flap.The closure attachment shown in FIG. 5 operates in the same manner asthe closure attachment shown in FIGS. 1-4 and 6.

The installation of the attachment shown in FIG. 5 is very simple.First, drainage openings 56 are drilled through the wall of cylindricalexhaust pipe 12 at diametrically opposed positions. Next, with flaps 2h,24 open and providing grasping surfaces, ring 30' is inserted down intoexhaust pipe 12 and rotated if necessary until its drainage openings 54are in alignment with drainage openings 56. Then a slender bolt, wire,stick, etc. is inserted through both sets of matched openings 54, 5s andused to temporarily hold ring 31] in place while the openings for screws48 are drilled and such screws are themselves installed, Stop means 58,6d are then installed, and the slender bolt, etc. is removed. As analternative arrangement, assuming that a slender bolt is used totemporarily anchor ring 33' in place, after screws 48 are installed, apair of diametrically opposed openings are drilled through pipe 12'above pin 18' and the slender bolt is installed therein to serve as thestop means in place of screws 53, 613.

Further modifications in form of the exhaust pipe closure mechanism ofthe present invention include making such closure means a permanent partof the exhaust pipe 12 rather than in the form of an attachment. This issimply done by mounting the respective ends of pin 18 directly throughthe wall of pipe 12, welding gutter 34 at its ends directly to theinterior surface of pipe 12, and securely fastening the seat formingmember or members and the stop means directly to the interior surface ofpipe 12, as by welding, for example. Thus, the term duct member is usedherein to mean either the attachment 1% or the exhaust pipe 12.

The foregoing is to be considered as merely illustrative of thestructural embodiments incorporating the principles of the presentinvention, and is therefore to be construed as not limitative in nature.Since changes, variations, and modifications in the form, construction,and the arrangement of the closure mechanisms shown and described may behad without departing from the spirit of the invention, it is to beunderstood that the invention is to be limited solely by the scope ofthe appended claims.

Having thus described the invention, what I claim is:

1. In combination with a vertically extending duct member forming a partof an internal combustion engine exhaust system through which hotexhaust gases flow, and having an open upper end, closure meanscompletely contained in duct member, said closure means comprising: apin extending across the interior of said duct member a substantialdistance down from its upper end; a first closure flap in said ductmember having a free outboard edge portion; first hinge means mountingsaid first closure flap onto said pin, for free pivotal movementthereabout on one side of the pin; a second closure flap in said ductmember having a free outboard edge portion; second hinge means mountingsaid second closure flap onto said pin, for free pivotal movementthereabout on the opposite side of the pin; seat means for underlyingand supporting the outer edge portions of said first and second closureflaps, and preventing downward pivotal movement of said closure flapsbeyond a predetermined, substantially horizontal, closed position; andstop means extending radially inwardly from the wall or" said ductmember above at least a portion of said pin, and between said closureflaps, said stop means serving to prevent movement of either closureilap from a substantially vertical open position towards thesubstantially horizontal closed position or" the other closure flap, andwith movement of said closure flaps from their closed to their openpositions being effected during engine operation by the exhaust gasesflowing upwardly through said duct member, and with closure of saidclosure flaps being effected by gravitational return of the closureflaps to their substantially horizontal closed positions whenever theexhaust gases cease to flow through said duct member.

2. The combination of claim 1, further including a heat shield memberextending laterally across said duct member below said pin and saidhinge means, said member having side portions meeting to form a bottom,and diverging apart as they extend upwardly from said bottom, said heatshield member serving to divert the hot exhaust gases around the pin andthe hinge means.

3. In combination with a vertically extending duct member forming a partof an internal combustion engine exhaust system through which hotexhaust gases flow, duct closure means contained entirely in said ductmember and comprising: a pin extending across the interior of said ductmember at a substantial distance below its upper end; a firstclosuremember in said duct member, and having a free outboard edge portion;first hinge means formed integral with said first closure member, andmounting same onto said pin for free pivotal movement thereabout; asecond closure member in said duct memher, and having a free outboardedge portion; second hinge means formed integral with said secondclosure member, and mounting same onto said pin for free pivotalmovement thereabout; said second hinge means being in substantial axialalignment with said first hinge means, with slight clearances existingbetween the joining portions of said first and second hinge means,between the first hinge means and the second closure member, and betweenthe second hinge means and the first closure memher; battle meansextending laterally across the interior of said duct member below saidpin and said clearances, and being connected at its ends with said ductmember, said bafi'ie means serving to shield and in that manner protectsaid hinge means and said pin from exhaust gas heat during engineoperation; seat means below the outboard edge portions of the closuremembers for preventing downward pivotal movement of the closure membersbeyond a substantially horizontal closed position, with the outboardedge portions of said closure members lying contiguous the wall of saidduct member above said seat means when the closure members occupy closedpositions; and stop means extending substantially radially inwardly fromthe wall of said duct member above at least a portion of said pin, andbetween said closure members, said stop "'5 means serving to preventmovement of either closure member from a substantially vertical openposition toward the substantially horizontal closed position of theother closure member, with movement of said closure members from theirclosed to their open positions being eifected during engine operation bythe exhaust gases flowing upwardly through said duct member, and withclosure of said closure members being effected by gravitational returnof the closure members to their substantially horizontal positionswhenever the exhaust gases cease to flow through said duct member.

4. The combination of claim 3, wherein said bafiie means comprises anupwardly opening trough, wherein at least one drainage opening isprovided in the wall of said duct member in the vicinity of at least oneend of said trough, and said trough serves, in addition to protectingsaid hinge means and said pin from exhaust gas heat during engineoperation, to collect and dispose of moisture which leaks through saidhinge clearances during engine shutdown.

5. In combination with a vertically extending, cylindrical duct memberforming a part of an internal combustion engine exhaust system throughwhich hot exhaust gases flow, closure means comprising: a pin extendingacross the interior of said cylindrical duct member and connecting atits respective ends with diametrically opposed Wall portions of saidcylindrical duct member; a first generally semi-circular closure flaphaving a free outboard edge portion and an inboard hinge portion curlingabout said pin, and serving to mount said first closure flap onto saidpin for free pivotal movement thereabout; a second generallysemi-cylindrical closure flap having a free outboard edge portion and aninboard hinge portion curling about said pin, and serving to mount saidsecond closure flap onto said pin for free pivotal movement thereabout;and a generally cylindrical member fitting snugly in said cylindricalduct member, and having an upper edge surface forming a seat for saidfirst and second closure flaps; and stop means extending substantiallyradially inwardly from the Wall of the duct member above at least aportion of said pin, and between said closure flaps, said closure flapsbeing freely pivotally moveable between closed positions, wherein theyrest upon said seat, and substantially vertical open positions, whereinthey rest against the stop means, with said stop means serving toprevent movement of either closure fiap from its open position towardthe closed position of the other closure flap, with movement of saidclosure flaps from their closed to their open positions being efiectedduring engine operation by the. exhaust gases flowing upwardly throughsaid duct member, and with closure of said flaps being effected bygravitational return of the flaps to their closed positions, upon saidseat, Whenever the exhaust gases References fitted by the ExaminerUNlTED STATES PATENTS 12/54 Great Britain.

EDWARD J. MECHAEL, Primary Examiner.

ROBERT A. OLEARY, Examiner.

1. IN COMBINATION WITH A VERTICALLY EXTENDING DUCT MEMBER FORMING A PARTOF AN INTERNAL COMBUSTION ENGINE EXHAUST SYSTEM THROUGH WHICH HOTEXHAUST GASES FLOW, AND HAVING AN OPEN UPPER END, CLOSURE MEANSCOMPLETELY CONTAINED IN DUCT MEMBER, SAID CLOSURE MEANS COMPRISING: APIN EXTENDING ACROSS THE INTERIOR OF SAID DUCT MEMBER A SUBSTANTIALDISTANCE DOWN FROM ITS UPPER END; A FIRST CLOSURE FLAP IN SAID DUCTMEMBER HAVING A FREE OUTBOARD EDGE PORTION; FIRST HINGE MEANS MOUNTINGSAID FIRST CLOSURE FLAP ONTO SAID PIN, FOR FREE PIVOTAL MOVEMENTTHEREABOUT ON ONE SIDE OF THE PIN; A SECOND CLOSURE FLAP IN SAID DUCTMEMBER HAVING A FREE OUTBOARD EDGE PORTION; SECOND HINGE MEANS MOUNTINGSAID SECOND CLOSURE FLAP ONTO SAID PIN FOR FREE PIVOTAL MOVEMENTTHEREABOUT ON THE OPPOSITE SIDE OF THE PIN; SEAT MEANS FOR UNDERLYINGAND SUPPORTING THE OUTER EDGE PORTIONS OF SAID FIRST AND SECOND CLOSUREFLAPS, AND PREVENTING DOWNWARD PIVOTAL MOVEMENT OF SAID FLOSURE FLAPSBEYOND A PREDETERMINED, SUBSTANTIALLY HORIZONTAL, CLOSED POSITION; ANDSTOP MEANS EXTENDING RADIALLY INWARDLY FROM THE WALL OF SAID DUCT MEMBERABOVE AT LEAST A PORTION OF SAID PIN, AND BETWEEN SAID CLOSURE FLAPS,SAID STOP MEANS A SUBSTANTIALLY VERTICAL OPEN POSITION TOWARDS THESUBSTANTIALLY HORIZONTAL CLOSED POSITION TOWARD THE SUBSTANTIALLYHORIZONTAL CLOSED POSITION OF THE OTHER CLOSURE FLAP, AND WITH MOVEMENTOF SAID CLOSURE FLAPS FROM THEIR CLOSED TO THEIR OPEN POSITIONS BEINGEFFECTED DURING ENGINE OPERATION BY THE EXHAUSE GASES FLOWING UPWARDLYTHROUGH SAID DUCT MEMBER, AND WITH CLOSURE OF SAID CLOSURE FLAPS TOTHEIR SUBSTANTIALLY HORIZONTAL CLOSED POSITIONS WHENEVER THE EXHAUSTGASES CEASE TO FLOW THROUGH SAID DUCT MEMBER.